SECTION 15950 - HVAC CONTROLS AND SEQUENCE OF OPERATIONS by wio18411

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									      SECTION 15950 - HVAC CONTROLS AND SEQUENCE OF OPERATIONS

                           City of San Diego, CWP Guidelines

PART 1 -- GENERAL

1.1   WORK OF THIS SECTION

 A.   The WORK of this Section includes providing equipment and devices required for a
      complete HVAC control system, including electrical devices, and the following:

      1.   Control system consisting of thermostats, control valves, dampers and operators,
           indicating devices, interface equipment and other apparatus and accessories
           required to operate mechanical systems, and to perform functions indicated.

      2.   Pneumatic automatic temperature control systems with electric accessories.

      3.   Sequence of operations for the HVAC equipment indicated.

1.2   RELATED SECTIONS

 A.   The WORK of the following Sections applies to the WORK of this Section. Other
      Sections of the Specifications, not referenced below, shall also apply to the extent
      required for proper performance of this WORK.

      1.   Section 11000   Equipment General Provisions
      2.   Section 15000   Piping Components
      3.   Section 15050   Vibration Isolation
      4.   Section 15410   Plumbing Piping
      5.   Section 15550   Water Tube Boilers and Accessories
      6.   Section 15750   Packaged Equipment
      7.   Section 15855   Air Handling and Moving Equipment
      8.   Section 15880   Air Distribution Devices and Accessories
      9.   Section 15990   Testing, Adjusting and Balancing

1.3   CODES

 A.   The WORK of this Section shall comply with the current editions of the following codes
      as adopted by the City of San Diego Municipal Code:

      1.   Uniform Mechanical Code

1.4   SPECIFICATIONS AND STANDARDS

 A.   Except as otherwise indicated, the current editions of the following apply to the WORK
      of this Section:

      1.   AMCA 500                  Test Methods for Louvers, Dampers and Shutters

      2.   ANSI/ASME B16.22          Wrought Copper and Copper Alloy Solder Joint
                                     Pressure Fittings

                                                      HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                    OF OPERATIONS
[CONTRACT NO.]-[CONTRACT NAME]                                             15950-1
      3.   ANSI/ASTM B32            Solder Metal

      4.   ANSI/NEMA 250            Enclosures for Electrical Equipment (1000 Volts
                                    Maximum)

      5.   ANSI/NFPA 90A            Installation of Air Conditioning and Ventilation Systems

      6.   ASTM B280                Seamless Copper Tube for Air Conditioning and
                                    Refrigeration Field Service

      7.   ASTM D1693               Environmental Stress - Cracking of Ethylene Plastics

      8.   FS-GG-G-76               Gauges, Pressure and Vacuum, Dial Indicating (for Air,
                                    Steam, Oil, Water, Ammonia, Chloro-
                                    Fluorohydrocarbon Bases, and Compressed Gases)

      9.   FS-QQ-S-571              Solder, Tin Alloy; Tin-Lead Alloy; and Lead Alloy

      10. MIL-F-18280               Fittings, Flareless Tube, Fluid Connection

      11. MIL-S-29175               Switch, Thermostatic, Low Voltage,                Non-
                                    (Setback/Setup) and Setback/Setup, Limiting

      12. NEMA DC 3                 Low-Voltage Room Thermostats

1.5   SHOP DRAWINGS AND SAMPLES

 A.   The following shall be submitted in compliance with Section 01300 in addition to the
      requirements of Section 11000:

      1.   Shop drawings indicating complete operating data, system drawings, wiring
           diagrams, and written detailed operational description of sequences; and
           arrangement, velocities, and static pressure drops, where automatic dampers are
           indicated, for each system.

      2.   Product data including description and engineering data for each control system
           components.

      3.   [Two] [    ] samples of [each type of room thermostat and cover] [thermostat
           guard] [each exposed control component].

1.6   PROJECT RECORD DOCUMENTS

 A.   The following shall be included in the PROJECT RECORD DOCUMENTS in compliance
      with Section 01300:

      1.   Accurate record of actual location of control components, including panels,
           thermostats, and sensors.

      2.   Revised shop drawings reflecting actual installation and operating sequences.


                                                     HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                   OF OPERATIONS
[CONTRACT NO.]-[CONTRACT NAME]                                            15950-2
1.7    OWNER'S MANUAL

 A.    The following shall be included in the OWNER'S MANUAL in compliance with
       Section 01300:

       1.   Systems descriptions, set points, and controls settings and adjustments.

       2.   Field reports indicating operating conditions after detailed check out of systems at
            Date of Substantial Completion.

       3.   Inspection period, cleaning methods, recommended cleaning materials and
            calibration tolerances

1.8    QUALIFICATIONS

 A.    The manufacturer and installer shall comply with the following:

       1.   Manufacturer: Company specializing in manufacturing the products indicated in
            this Section.

       2.   Installer: Company specializing in installing the WORK of this Section and
            approved by manufacturer.

1.9    SEQUENCING AND SCHEDULING

 A.    Installation of system components shall be coordinated with installation of mechanical
       systems equipment including air handling units, [packaged] air conditioning equipment
       and air terminal units.

1.10   MAINTENANCE SERVICE

 A.    The WORK of this Section includes:

       1.   Service and maintenance of automatic controls system for [one] [          ] year from
            Date of Substantial Completion.

       2.   [Two] [Four] [ ] complete inspections, to inspect, calibrate, and adjust controls
            as required, and submit written reports.

PART 2 -- PRODUCTS

2.1    PNEUMATIC AIR SUPPLY

 A.    The pneumatic air supply system shall include the following:

       1.   Air Supply and Receiver: [simplex] [duplex] belt driven air compressors and tank
            with belt guard, silencers, flexible connections, air filters, automatic and manual
            drain assemblies, oil and particle filter for minimum 0.5 micron particles, pressure
            reducing valves, and pressure relief valves. Compressors and storage tanks shall
            be sized to limit compressor starts to maximum [10] [         ] per hour and [50] [30]
            percent running time.


                                                          HVAC CONTROLS AND SEQUENCE
[DECEMBER 1995]                                                        OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                15950-3
      2.    Pressure Control: zinc or aluminum castings, rated for service with elastomeric
            diaphragm, adjustable electric contacts, set to start and stop compressor at [50
            and 65 psig] [60 and 80 psig] [70 and 90 psig] [100 and 125 psig][,] [and second
            compressor at [50 and 65 psig] [60 and 80 psig] [70 and 90 psig]].

      3.    Electrical Alternation Set: with motor starters to operate compressors [alternately]
            [on time schedule].

      [4.   Pressure Regulators: rated for service with elastomeric diaphragm, balanced
            construction to automatically prevent pressure buildup, and producing flat, reduced
            pressure curve for system capacity demand.]

      [5.   Particle Filters: rated for service with threaded connections, quick-disconnect
            service devices, aluminum bowl or plastic bowl with metal guard equipped with
            manual draincock, to separate liquid and solid particles.]

      [6.   Combination/Filter/Regulators: rated for service with elastomeric diaphragm,
            designed and constructed to automatically prevent pressure buildup, and to
            produce flat, reduced pressure curve for system capacity demand; with threaded
            pipe connections, quick-disconnect service devices, aluminum bowl or plastic bowl
            with metal guard equipped with manual draincock to separate liquid and solid
            particles.]

      7.    Airborne Oil Filter: rated for service with filtration efficiencies of 99.9 percent for
            particles of 0.025 micron or larger of airborne lubricating oil.

      8.    Pressure Relief Valves: ASME Code Rated and Labeled for high pressure side
            and sized for installed capacity of pressure regulators at low pressure; valves shall
            be set at maximum 20 percent above low pressure.

2.2   CONTROL AND INSTRUMENTATION TUBING

 A.   Control and instrumentation tubing, fittings and joints shall comply with the following:

      1.    Copper Tubing: ASTM B280, Type K, seamless, hard drawn or annealed.
              Fittings:   ANSI/ASME B16.22, wrought copper, solder type.
                  Joints: ANSI/ASTM B32 [or FS QQ-S-571 alloy 58-5] [95-5]
                          [60-4] tin antimony.

      2.    Copper Tubing: ASTM B280, Type K, seamless, hard drawn or annealed.
              Fittings:   UL approved [to MIL-F-18280] rod or forged brass rated to 200 psig
                          at 100 degrees F (1380 kPa at 38 degrees C).
                  Joints: ball sleeve compression type.

      3.    Polyethylene Tubing: Black, flame retardant, virgin polyethylene, conforming to
            modified ASTM D1693 test.
                 Fittings: UL approved [to MIL-F-18280] rod or forged brass rated to 200 psig
                           at 100 degrees F (1380 kPa at 38 degrees C).
                 Joints: Compression or barbed type.




                                                           HVAC CONTROLS AND SEQUENCE
[DECEMBER 1995]                                                         OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                 15950-4
2.3   REFRIGERATED AIR DRYER

 A.   The refrigerated air dryer shall comply with the following:

      1.   Dryers: commercial quality, refrigerated, compressed air dryer complete with heat
           exchangers, moisture separator, and internal wiring and piping and including air
           inlet and outlet connections connected through manual by-pass valve.

      2.   Heat Exchangers: air to refrigerant coils including centrifugal type moisture
           separator located at discharge of compressed air complete with automatic trap
           assembly; and with automatic control system to bypass refrigeration system on low
           or no load conditions.

      3.   Refrigeration Unit: hermetically sealed, operating to maintain dew point of [5] [13]
           [ ] degrees F at 20 psig and housed in steel cabinet with access door and panel.

      4.   Accessories: air inlet temperature gauge, air inlet pressure gauge, on/off switch,
           high temperature light, power on light, refrigeration gauge, air outlet temperature
           gauge, air outlet pressure gauge.

2.4   THERMOSTATS

 A.   Control systems shall include the following:

      1.   Pneumatic Room Thermostats: adjustable proportioning type, [single] [dual]
           setpoint, containing [single bimetallic element for heating or cooling only] [dual
           bimetallic elements for] [heating and cooling] [day or night], minimum 10 degrees F
           set point adjustment[;] [and] adjustable dead band;] and including locking covers
           with [set point adjustment,] [setpoint indication,] [concealed setpoint,] [with
           thermometer.] [without thermometer.]

      2.   Room Thermostat Accessories:
               Thermostat Covers: [brushed aluminum.] [      .]
               Insulating Bases: for thermostats located on exterior walls.
               Thermostat Guards: [metal] [locking transparent plastic] [           ] mounted
                                    on separate base.
               Adjusting Key: as required for thermostat.

      3.   Outdoor Reset Thermostat: remote bulb or bimetal rod and tube type, for
           proportioning action with adjustable throttling range; scale range of [-10 to 70
           degrees F [        ] with adjustable setpoint.

      4.   Immersion Thermostat: remote bulb or bimetallic rod and tube type, for
           proportional action with adjustable setpoint and adjustable throttling range.

      5.   Airstream Thermostats: remote bulb or bimetallic rod and tube type, for
           proportional action with adjustable setpoint in middle of range and adjustable
           throttling range.

      6.   Fire Thermostats: UL approved and listed, factory set in accordance with
           ANSI/NFPA 90A with normally closed contacts, manual reset.


                                                        HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                      OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                              15950-5
      7.   Heating/Cooling Valve Top Thermostats: proportional acting for proportional flow,
           molded rubber diaphragm, [remote bulb] liquid filled element, direct and reverse
           acting at differential pressures to 25 psig, cast housing with position indicator and
           adjusting knob.

2.5   CONTROL VALVES

 A.   Control valves shall comply with the following:

      1.   Globe Pattern:

                 Up to 2 inches: bronze body, bronze trim, rising stem, renewable
                 composition disc, screwed ends[,] [with backseating capacity repackable
                 under pressure].

                 Over 2 inches: iron body, bronze trim, rising stem, plug-type disc, flanged
                 ends, renewable seat and disc.

      2.   Butterfly Pattern: iron body, [bronze] [aluminum bronze] [stainless steel] disc,
           resilient replaceable seat for service to [180 degrees F] [250 degrees F] wafer or
           long ends, extended neck.

      3.   Operators:
               Rolling diaphragm, spring loaded, piston type with spring range [2 to 5 psig]
               [3 to 10 psig] [8 to 11 psig] [as indicated].
               Valves shall spring return to normal position as indicated on freeze, fire, or
               temperature protection.

      4.   Hydronic Systems:
                Rated for service pressure of 125 [ ] psig at 250 degrees F.
                Replaceable plugs and seats of [stainless steel] [brass].
                Sized for [3] [   ] psig maximum pressure drop at design flow rate.
                Two way valves shall have equal percentage characteristics and three way
                valves shall have linear characteristics. Two way valve operators shall be
                sized to close valves against pump shut-off head.

2.6   DAMPERS

 A.   Dampers shall comply with the following:

      1.   Performance: tested in accordance with AMCA 500.

      2.   Frames: [galvanized steel] [extruded aluminum] [rolled corner steel] [stainless
           steel], welded or riveted with corner reinforcement.

      3.   Blades: [galvanized steel] [extruded aluminum] [rolled carbon steel] [stainless
           steel], maximum blade size [     ] inches wide, [    ] inches long, attached to
           minimum 1/2 inch shafts with set screws.

      4.   Blade Seals: [synthetic elastomeric] [neoprene] [inflatable] mechanically attached,
           field replaceable.


                                                         HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                       OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                               15950-6
      5.    Jamb Seals: stainless steel.

      6.    Shaft Bearings: [oil impregnated sintered bronze or graphite impregnated nylon
            sleeve, with thrust washers at bearings;] [lubricant free, stainless steel, single row,
            unground, flanged, radial, antifriction type with extended inner race.]

      7.    Linkage Bearings: oil impregnated sintered bronze or graphite impregnated nylon.

      8.    Leakage: less than [one] [1/2] percent based on approach velocity of 2000 ft/min
            and 4 inches wg.

      9.    Maximum Pressure Differential: [        ] [6] inches wg.

      10. Temperature Limits: -40 to 200 degrees F.

2.7   TIME CLOCKS

 A.   Time clocks shall be:

      [1.   Seven day programming switch timer with synchronous timing motor and seven
            day dial, continuously charged Ni-cad battery driven power failure 8 hour carry over
            and multiple switch trippers to control systems for minimum of two and maximum
            of eight signals per day with two normally open and two normally closed output
            switches.]

      [1.   Solid state programmable time control with [         ] separate programs, 24 hour
            battery carry over[,] [.] [duty cycling] [individual on/off/auto switches for each
            program] [7 day programming] [365 day calendar with 20 programmable holidays]
            [choice of fail safe operation for each program] [system fault alarm].]

2.8   WATER TEMPERATURE CONTROLLERS

 A.   Controllers shall operate by adjustable differential over adjustable temperature range
      and shall be suitable for operating control valve indicated.

2.9   DAMPER OPERATIONS

 A.   Damper operators shall comply with the following:

      1.    General: smooth proportional control with sufficient power for air velocities 20
            percent greater than maximum design velocity and constructed to provide tight
            seal against maximum system pressures; with spring return for two position control
            and for fail safe operation.

      2.    Pneumatic Operators: rolling diaphragm piston type[.] [with adjustable stops.]

      3.    Pilot Positioners: starting point adjustable from [    ] [2] to [      ] [12] psig and
            operating span adjustable from [      ] [5] to [  ] [13] psig.

      4.    Electric Operators: split phase type with oil immersed gear train.



                                                           HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                         OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                 15950-7
       5.   Number: sufficient to achieve unrestricted movement throughout damper range;
            [and one damper operator for maximum 36 sq ft damper section.]

       6.   Inlet Vane Operators: high pressure with pilot positioners and sufficient force to
            move vanes when fan is started with vanes in closed position; and designed to
            return to closed position on fan shutdown.

2.10   TRANSMITTERS

 A.    Transmitters shall comply with the following:

       1.   Building Static Pressure Transmitter: one pipe, [direct acting, double bell,]
            differential type with temperature compensation, scale range [       ] [0.01] to [ ]
            [6.0] inch wg positive or negative, and sensitivity of 0.0005 inch wg and designed
            to transmit [electronic] [pneumatic] output.

       2.   Pressure Transmitters: one pipe direct acting [indicating type] for gas, liquid, range
            suitable for system, proportional [electronic] [pneumatic] output.

       3.   Temperature Transmitters: one pipe, directly proportional output signal to
            measure variable linearity within plus or minus 1/2 percent of range for [ ] [200]
            degree F span and plus or minus one percent for [       ] [50] degree F span, with
            [      ] [50,] [100,] or [200] degree F temperature range, compensated bulb,
            averaging capillary, or rod and tube operating on [ ] [20] psig input pressure and
            [   ] [3] to [    ] [15] psig output.

2.11   RECEIVER CONTROLLERS

 A.    Controllers shall comply with the following:

       1.   Controllers shall be single or dual input models [with control point adjustment]
            direct or reverse acting with mechanical set point adjustment [with locking device],
            and proportional band adjustment and with [proportional] [proportional plus integral]
            control mode.

       2.   Remote control point adjustment shall be plus or minus [20] [            ] percent of
            sensor span, input signal [3 to 13 psig] [1 to 20 psig].

       3.   Proportional band shall extend from 2-1/2 to 40 percent of primary sensor span.

       4.   Controllers shall be suitable for supply air pressure of [18 psig] [20 psig] with input
            signals of [3 to 15 psig] [1 to 20 psig] and output signal 0 to [15 psig] [20 psig].

2.12   PNEUMATIC SYSTEMS ACCESSORIES

 A.    Control systems shall include:

       1.   Pressure Gauges: manufacturer's standard [to FS-GG-G-76], black letters on
            white background, [3-1/2 inch] [2-1/2 inch] [2 inch] diameter, flush or surface
            mounted, with [front calibration screw,] suitable dial range calibrated to match
            sensor, in appropriate units.


                                                           HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                         OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                 15950-8
       2.   Instrument Pressure Gauges: manufacturer's standard [to FS-GG-G-76], black
            letters on white background, [2 inch] [1-1/2 inch] diameter, stem mounted with
            suitable dial range.

       3.   Diaphragm Control and Instrument Valves: 1/4 and 3/8 inch forged brass body
            with reinforced teflon diaphragm, stainless steel spring, and color coded phenolic
            handle.

       4.   Gauge Cocks: tee or lever handle, bronze, rated for 125 psig.

       5.   Relays: for summing, reversing, amplifying, highest or lowest pressure selection,
            with fixed 1:1 [or adjustable] input/output ration.

       6.   Switches: with indicating plates, accessible adjustment, calibrated and marked.

2.13   CONTROL PANELS

 A.    Control panels shall comply with the following:

       1.   Type: unitized cabinet type for each system under automatic control with relays
            and controls mounted in cabinet and temperature indicators, pressure gauges, pilot
            lights, pushbuttons and switches flush on cabinet panel face.

       2.   Standards: ANSI/NEMA 250, general purpose utility enclosures with enamelled
            finished face panel.

2.14   ALARM SYSTEM

 A.    Alarm panels shall comply with the following:

       1.   Alarm panel shall include individual indication, horn, silenced acknowledge switch,
            and test switch.

       2.   At any alarm condition, indication light shall flash and alarm shall sound; horn shall
            be stopped by depressing acknowledge switch and shall indicate alarm conditions
            by a continuous light until trouble condition has cleared; alarm shall sound again
            should second alarm occur before first one has cleared.

       3.   Remote panels, where indicated, shall include indication horn, activated by any
            alarm and alarm silence/acknowledge switch such that alarm can be
            acknowledged from master and remote panel.

       4.   Panels shall be located as indicated to serve duplicate functions of primary panel
            and shall include alarm silence/acknowledge switch such that alarm can be
            acknowledged from any panel.

       5.   Dry contacts shall be included at main alarm panel for use by independent alarm
            monitoring company to indicate [each] alarm condition.




                                                          HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                        OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                15950-9
2.15   MANUFACTURERS

 A.    Products shall be manufactured by one of the following (or equal):

       1.   General Controls
       2.   Honeywell
       3.   Johnson Controls Co.

PART 3 -- EXECUTION

3.1    INSTALLATION

 A.    General: Controls and components shall be installed in accordance with the
       manufacturer's written installation instructions and as follows:

       1.   Compressor and tank shall be mounted on vibration isolation[.] [consisting of
            springs, with minimum [1 inch] [2 inches] static deflection and one inch clearance
            to floor.] Air supply shall be isolated with wire-braid reinforced rubber hose[.] [or
            polyethylene tubing.]

       2.   Instrument air shall be supplied from compressors through filter, pressure reducing
            valve, pressure relief valve, with pressure gauges, and shutoff and bypass valves.

       3.   Pressure reducing stations consisting of pressure reducing valve, particle filter,
            valved bypass, pressure gauge on inlet and outlet, and pressure relief valve shall
            be installed.

       4.   Refrigerated air dryer shall be located in discharge air line from tank; dryer shall
            be mounted on wall on rubber in shear mounts; pressure regulator shall be
            installed downstream of dryer; and automatic drain shall be piped to nearest floor
            drain.

       5.   Copper tubing shall be installed in mechanical rooms, where subject to damage
            or temperatures in excess of 200 degrees F, where adjacent to heating pipes
            passing through common sleeve and where not readily accessible; in mechanical
            rooms, bundled plastic tubing with suitable junction boxes or single plastic tubing
            with tray or raceway may be used.

       6.   Tubing shall be concealed and exposed only in mechanical rooms, storage rooms
            and like, in neat manner and shall be properly supported.

       7.   Tubing shall be attached to supporting surfaces; sleeve shall be provided through
            concrete surfaces in minimum one inch sleeves, extended 6 inches above floors
            and 1 inch below bottom surface of slabs.

       8.   Tubing shall be purged with dry, oil-free compressed air before connecting control
            instruments.

       9.   [Pressure gauges] [Test plugs] shall be installed on branch lines at each receiver
            controller and signal lines at each transmitter excepting individual room controllers.



                                                          HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                        OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                               15950-10
      10. Location of thermostats and other exposed control sensors shall be verified with
          plans and room details before installation; room thermostats shall be located [60
          inches] [48 inches] [42 inches] above floor; lighting switches shall be aligned.

      11. Freeze protection thermostats shall be mounted using flanges and element
          holders.

      12. Outdoor reset thermostats shall be mounted with sensing elements outdoors[.]
          [with sun shield.]

      13. Separable sockets shall be installed for liquids and flanges for air bulb elements.

      14. Guards shall be located on thermostats in entrance hallways [and other public
          areas.] [and where indicated.]

      15. Control panels shall be mounted adjacent to associated equipment on vibration
          free walls or free standing angle iron supports. One cabinet may accommodate
          more than one system in same equipment room but shall include engraved plastic
          nameplates for instruments and controls inside cabinet and engraved lamicoid
          nameplates on cabinet face.

      16. "Hand/off/auto" selector switches shall be installed to over-ride automatic interlock
          controls when switch is in "hand" position.

      17. Conduit and electrical wiring shall be installed where required.

      18. After completion of installation, control equipment shall be tested and adjusted.

      19. Pneumatic systems shall be tested to system pressure maximum of [          ] [30] psig
          and calibration of instruments shall be checked.

3.2   SEQUENCE OF OPERATIONS

 A.   Control systems shall be installed to provide for the Sequence of Operations indicated.

 B.   Fan Coil Units:

      [1.   [Single] [Dual] temperature thermostat set at [75] [   ] degrees F shall maintain
            constant space temperature [during the day and [15] [        ] degrees F cooler at
            night] by [modulating] [opening and closing] two-way control heating valve [with
            spring range of 3 to 7 psig] [and two-way cooling control valve] [with spring range
            of 8 to 13 psig] in sequence.]

      [2.   [Single] [Dual] temperature thermostat set at [75] [     ] degrees F shall maintain
            constant space temperature [during the day and [15] [         ] degrees F cooler at
            night] by modulating four-way control valve; during heating cycle, thermostat shall
            modulate hot water supply to coil and divert return water to heating return pipe;
            during cooling cycle, thermostat shall modulate chilled water supply to coil and
            divert return water to cooling return pipe; when space temperature is at thermostat
            setting, flow shall be prevented from occurring in either circuit and in coil.]



                                                        HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                      OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                             15950-11
            3.   Change over from heating to cooling shall be by indexing thermostat from
                 thermostat on supply piping; when supply is above room temperature, thermostat
                 shall operate in direct acting manner, opening valve when temperature falls below
                 thermostat setting; when supply is below room temperature, thermostat shall
                 operate in reverse acting manner, opening valve when space temperature rises
                 above thermostat setting.

            4.   For heating and cooling fan coil units with fan speed control during heating cycle,
                 fan speed shall increase as space temperature falls below thermostat setting when
                 hot water is available; during cooling cycle, fan speed shall increase as space
                 temperature rises above thermostat setting when chilled water is available.

            5.   Thermostat with adjustable knob and speed switch shall be mounted on common
                 plate with "Heating Control and Fan Control" on top, with "Warmer and Cooler".

 C.      Electrical Rooms and Telephone Rooms:

         1.      On room temperatures above [95] [        ] degrees F [intake dampers shall open
                 and] exhaust fans shall start.

 D.      Elevator Machine Rooms:

   [1.           On room temperatures above [85] [      ] degrees F, intake dampers shall open and
                 exhaust fan shall start.

      [2.        On room temperatures above [90] [        ] degrees F, audible alarm shall signal].

 E.      Emergency Generator:

         1.      Air Cooled Generator

                      When generator is "off", outside and exhaust dampers shall be closed and
                      recirculation damper shall be open.

                      When generator is "on", dampers shall be controlled and operate with
                      outside and exhaust dampers opening, and recirculating dampers closing,
                      to maintain room temperature of [85] [ ] degrees F.

         2.      Water Cooled Generator

                      On room temperatures above [95] [          ] degrees F intake dampers shall
                      open and exhaust fans shall start.

 F.      Unit Heaters:

         1.      Hot Water Coils

                      Single temperature electric room thermostat shall maintain constant space
                      temperature of [68] [   ] degrees F by cycling unit fan motor.




                                                             HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                           OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                                  15950-12
                 Single temperature thermostat on return heating water line [from floor
                 mounted cabinet heaters] shall de-energize unit on temperatures below [95]
                 [   ] degrees F.

      2.   Electric Space Heaters

                 Single temperature room thermostat set at [68] [  ] degrees F shall
                 maintain constant space temperature by cycling unit fan motor and
                 energizing electric heating elements.

 G.   Terminal Air Units:

      1.   Constant Volume

                 [Single] [dual] temperature thermostat set at [75] [        ] degrees F shall
                 maintain constant space temperature [during the day and [15] [              ]
                 degrees F cooler at night] by [modulating] [opening and closing] two-way
                 control heating valve [with spring range of] [3 to 7 psig] [3 to 13 psig.]

      2.   Variable Air Volume

                 [Single] [Dual] temperature thermostat set at [75] [    ] degrees F shall
                 maintain constant space temperature by modulating variable volume damper
                 operator.

 H.   Heating Water Zone Control:

      1.   Hot Water Pump

                 [Flow] [Pressure] switch in heating pump discharge shall indicate "on/off".

      2.   Indoor/Outdoor Controller

                 Heating water shall control supply temperature [set at [195] [ ] degrees F]
                 [in accordance with outdoor reset schedule] by modulating heating water
                 control valve.

      3.   Outdoor Reset

                 Heating water shall be controlled at maximum [195] [     ] degrees F at
                 outdoor temperature of [  ] degrees F, and minimum [130] [    ] degrees
                 F at outdoor temperature of [75] [       ] degrees F, with straight line
                 relationship.

 I.   Heating and Cooling With 4-Way Control Valve:

      1.   [Single] [Dual] temperature thermostat set at [75] [     ] degrees F shall maintain
           constant space temperature [during the day and [15] [          ] degrees F cooler at
           night] by modulating four-way control valve; during heating cycle, hot water supply
           to coil shall be modulated and return water shall be diverted to heating return pipe;
           during cooling cycle, chilled water supply shall be modulated to coil and return
           water shall be diverted to cooling return pipe; when space temperature is at

                                                        HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                      OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                             15950-13
           thermostat setting, flow shall be prevented from occurring in either circuit and in
           coil.

      2.   Change over from heating to cooling shall be by indexing thermostat from aquastat
           on supply piping; when supply is above room temperature, thermostat shall
           operate in direct acting manner, opening valve when temperature falls below
           thermostat setting; when supply is below room temperature, thermostat shall
           operate in reverse acting manner, opening valve when space temperature rises
           above thermostat stetting.

      3.   Single temperature room thermostat set at [75] [      ] degrees F shall maintain
           constant space temperature by [energizing] [staging] [modulating electric output
           through action at SCR power controller, to] electric heaters.

 J.   VENTILATION SYSTEMS IN CORROSIVE ENVIRONMENTS

      1.   Where corrosive environments (including process areas using chlorine, sulfur
           dioxide and hydrogen sulfide) are indicated, ventilation systems shall comply with
           the following:

                Gas monitor shall activate audible alarms located both adjacent to process
                areas and in Administration Area.

                Gas monitor shall signal light in control panel in Administration Building.

3.3   CONTROL DAMPER AND CONTROL VALVE SCHEDULES

 A.   Control dampers shall comply with the requirements indicated on the attached Control
      Damper Schedule.

 B.   Control valves shall comply with the requirements indicated on the attached Control
      Valve Schedule.

3.4   DEMONSTRATION

 A.   The WORK of this Section includes demonstration to the OWNER and
      CONSTRUCTION MANAGER of complete operation of systems, including sequence
      of Operation after Date of Substantial Completion.

                                 ** END OF SECTION **




                                                       HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                                     OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                            15950-14
                             CONTROL DAMPER SCHEDULE




Equipment I.D. Number                          [CD-1]               [CD-2]



Drawing Reference

Location

Height, inch

Width, inch

Air Flow, CFM

Air Pressure Drop, inch wg

Damper Operator




                                              HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                            OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                                   15950-15
                        CONTROL VALVE SCHEDULE




Equipment I.D. Number                     [CV-1]          [CV-2]



Drawing Reference

Location

Valve Size, inch

Valve CV

Operator Spring Range

Normal Position

Valve Operator




                                         HVAC CONTROLS AND SEQUENCE
[FEBRUARY 1991]                                       OF OPERATIONS
[CONTRACT NO.]-[CONTRACT TITLE]                              15950-16

								
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